The present invention relates to pincers, tweezers, forceps and analogous instruments in general, and more particularly to improvements in instruments which are especially suited for use by surgeons (particularly for use in microsurgery) or for analogous purposes. Still more particularly, the invention relates to improvements in forceps-like or analogous instruments with two elongated legs and with means for guiding the legs during movement to their closed positions and/or for determining the closed positions.
It is already known to provide the legs of pincers, tweezers, forceps or analogous instruments (hereinafter called instruments for short) with guide means which ensure that the tips or working ends of the legs engage each other in closed positions of the legs and which start to guide the legs once the legs complete a certain movement from their fully open or spaced-apart positions. Such guide means serve to prevent tilting, shifting, jamming and/or other undesirable stray movements of the legs, for example, movements which would result in one of the tips bypassing the other tip in fully closed positions of the legs. A drawback of such conventional guide means is that they cannot invariably ensure proper guidance of the one and/or the other leg during each and every stage of movement of the tips of the two legs toward or away from each other. For example, twisting or analogous forces acting upon one or both legs during the initial stage of movement of the two legs to their closed positions (namely, during that stage when the conventional guide means is not as yet in action) can entail such deformation of one or both legs that the guide means cannot become effective at all and the tip of one of the legs bypasses the tip of the other leg during the last stage of movement of the legs to closed positions. Such pronounced deformation of one or both legs can result in total inability of the working ends or tips of the legs from moving into actual engagement with one another. A surgeon's work, e.g., in the course of complex brain surgery, is greatly impeded by any misalignment of the legs of a forceps, and the misaligned tips of the two legs can cause damage to tissue or to other substances or body parts of the patient.